Illuminated sign



July 15, 1930.

ILLUMINATED IGN Gets-S l y 1930. R. M. cRAl-s 1,770,391

ILLUMINATED SIGN Filed Aug. 6, 1929 2 Sheets-Sheet 2 5 wucntop 1?. M Cra20 desirable, in fact, necessary,

Patented July 1-5, 1930 UNITED I sTATas RICHARD M. CRAIG, OF SANANTONIO, TEXAS ILLUMINATED SIGN Application filed August 6, 1929. SerialNo. 883,907.

Owing to the delicate nature and frangibil-' ity of neon and otherluminescenttubes used in the manufacture and installation of signs fordisplay purposes, considerable difficulty 5 has been experienced inshipping or transporting the tubes from the factory to the point ofinstallation. Furthermore, these tubes in the course of manufacture aregenerally bent, molded or twisted to form the letters of the word orsign to be displayed and, if, after the tubes are secured in position onthe sign, a fracture or breakage occurs in one of the letters of thesign, it necessitates bodily removal of the sign, reshipment to thefactory for repairs or replacement and a new installation of therepaired letters. As a result of the difliculty in shipping the delicatetubes from distant points to the place of installation, it has beenfound to equip a factory in the town or city where numerous signs aredisplayed. This necessarily entails considerable expense and,furthermore, requires a force of workmen constantly in attendance 5 toremove and replace the tubes when they become broken, fractured orotherwise impaired.

The object of'tbe present invention is toform neon or other luminescenttubes at the so factory in standardized units, each Unit mm sisting of aplurality of superposed folds o1" coils disposed in parallel relationand in intimate proximity to each other, each bank of folded or coiledtubes constituting a unit as serving to display a word or a plurality ofletters constitutlng one or more words. This result is accomplished bymaking a stencil and placing it over the luminescent tube unitsin such amanner that one or more of the words 40' to be advertised or displayedwill appear through the stencil at each unit. In other words, onlyportions of the tubes of each unit will be visible through the stencilforming the letters or words to be-displayed, the

remaining portion of the tubes of each unit being obscured by the opaqueimperforate body of the stencil. In this manner, any desired wording oradvertising may be made to appear on the sign by merely changing thenature or character of the stencil'and with out the expenseof blowing,bending or otherwise forming the tubes into the desired letters orcharacters as heretofore has been the practice. The sign may be changedvevery day by merely putting on a new stencil Without the necessityofremoving or in any wise disturbing the banks of tubes. Furthermore,inasmuch as the several banks of luminescent units are firmly securedtothe background of the sign, liability of breakage or displacec0 mentof the uni-ts is reduced to a minimum, but should such breakage occur inany one of said units, it may be readily removed at a moments notice byan unskilled workman and said damaged unit or units replacedo'a withoutthe necessity of shipping the sign to the factor" for replacement ofparts.

One em odiment of the invention is illustrated in the accompanyingdrawings and will be hereinafter fully described, the novel featuresbeing particularly pointed out in the appended claims.

In the drawings:

Figure 1 is a erspective view, with parts broken away, 0 a signembodying the pres- 75 ent invention,

Fig. 2 is a front elevation with the stencil plate removed,

'Fig.- 3 is ahorizontal section on theline 3-3 of Fig. 2,

Fig. 4 is a detail perspective showing one of the illuminating unitsremoved, and

Fig.5 is a detail illustrating one effect producedwhen the sign is inuse.

In carrying out the present invention, there. is shown a base 1 uponwhich is mounted a motor 2 and a housing 3 within which is arrangedgearing for rotating the si n, and

break electrical conductors and make an devices for controlling theillumination. The

-mechanism includes a shaft 4 which is rotatably mounted in the upperportion of the housing and frame, indicated as an entirety by thenumeral 3, and upon the front end of this'shaft is secured a rotatinghead or support 5, said support being shown as a circular disk having. arim 6 around its margin andhaving partitions 7 extending across itsouter surface, as indicated in Figs. 1 and 2, the disk and saidpartitions being of some opaque lite gas being shown in non-conductingmaterial. The disk or head is secured to the shaft through the medium ofa junction box or hub 8 and the shaft is hollow to permit the wirescarrying current to the illuminating tubes to pass through the shaft andto rotate With the shaft, brushes and collector rings being employed ina well known manner to establish the electric connection between themovable conductors and the stationary conductors. Removably secured uponthe outer edge of the marginal rim 6 is a cap plate of stencil 9 havingopenings 10 formed therethrough, which openings are so arranged as toproduce letters, words or other characters, the words Flash theaccompanying drawings by way of example.

Secured upon the disk 5 between the partitions 7 and between thepartitions and the rim are luminescent tubes 11 which, in the presentinstance, are in the form of coils, each coil including a plurality ofstraight sections arranged closely together in parallelism and connectedalternately at their opposite ends by bent elbow portions, as clearlyshown. These tubes have their terminal electrodes 12 disposed entirelyin alinement with the respective portions from which they extend andparallel with the adjacent section of the coil so that the entire tubemay occupy a plane parallel with the face of the disk and no portion ofthe tube will have to pass through the disk in order to secure the tubein place. Neon tubes, as

. now made according to general practice, are

shaped to form letters or words or other characters, and in order tomount them upon a support, the terminal electrodes or end portions areturned at a right angle to the plane of the support and pass through thesupport and-are mounted upon springs or similar cushioning devices, thisarrangement being deemed necessary in order to avoid fracture of thetubes which are very thin and are easily broken. It is also nowgenerally considered that the tubes must be mounted in spring supportsas slight vibration will cause the tubes to fracture, and it has beengenerally considered, in a practical sense, that neon tubes must bemounted in a fixed position and cannot be employed in revolvingapparatus as they are very apt to shatter under centrifugal force.According to the present invention, the tubes are seated in blocks 13 ofwood or other analogous material, which blocks are secured to the faceof the disk, or to panels removably mounted thereon, and firmly held inplace by being coated with a cement having a cellulose base and havingthe same coeflicient of expansion as the luminescent tubes. This cementis applied over the seat of the several blocks so that the tubes will beseated in the cement and actual use has demonstrated that tubes thussupported will be very firmly held and the disk upon which the tubes aremounted may be rotated with the tubes at a high speed without causingany breakage or dislocation of the tubes. Each tube unit is preferablymounted upon a panel 14 which is of a size and form to fit nearly withina division of the supporting head defined by the margin 6 and apartition 7 and removably held therein by screws or similar fasteningdevices 15 inserted through openings provided therefor at the corners ofthe panel to engage in the disk 5, as will be understood.

In the particular example of the invention shown in the drawings, thestencil or cap plate 9 has three words out therein and thetube-supporting head is divided into three sections or compartments bythe partitions 7 the parts being so arranged that each word in thestencil plate will be coordinated with one tube unit in the head. Theunits are illuminated electrically in the usual manner and are filledwith a gas which will impart to the tube a distinctive color whenlighted. The shaft 4 is rotated at a relatively high speed and thecurrent to the several tube units is controlled by make and break devices operating at a lower speed and which may be of any approvedarrangement and construction. An example of such mechanism may be seenin my copending application for patent Serial No. 383,908, filedsimultaneously herewith. In my co-pending application as well as in thepresent application, the head carrying the lighted or illuminated tubesis rotated continuously thereby causing the letters of the words Flashlite gas to apparently intermingle and form an artistic geometricalfigure or design and when the tubes are of different colors the artisticeffect of the dis layed design will be materially enhanced. t a certainperiod in the revolution of the head, the current is intermittently cutoff and on and always at the same point of revolution of said head sothat instead of the letters of the words forming a geometrical design,said words will be legibly displayed in a readable horizontal position.The luminescent tubes are free of afterglow so that they light and areextinguished instantly as the current is cut in or out and they operateonly on alternating current so that, while the effect upon the eye is ofa continuous light, actually the light is being rapidly turned on andoff. If as previously stated, the make and break de vices be in suchposition that the illumination of the tubes will occur only once duringeach revolution of the shaft and head and always occurs at the samepoint in the revolution, the 'persisten'cy of vislon 1n the eye causesthe eye to retain the impression of the flash of illumination of thetubes until the ensuing flash occurs so that the eye will obtain theeffect of a stationary sign having its words illuminated in readingposition.

" ings which form If, however, the makeiand break devices are .thepersistency ofvision in the eye causes the eye to retain the impressionof the illumination in one position overlapping the illumlnation in apreceding and also in a succeeding position so that the effect upon theeye is of a plurality of lines disposed in various angular relations tothe radii of the disk and overlapping each other so that a kaleidoscopicefl'ect is obtained. The de sign is produced by theapparent overlapping.of the light passing through the openthecharacters in the stencil plate.and, consequently, the designs produced by no two machines will be thesame unless the characters in the stencil plates of the two machines areidentical. A wide variety of effects can be obtained by introducing intothe tubes difl'erent gases and also by forming the tubes of glass ofdifferent colors, the gases ordinarily employed in'neon or luminescenttubes having the faculty of assuming color when the electric current ispassed throughthem and the color of the gas may be modified by varyingthe color ot the glass from which the tube is formed.

It is also possibleto vary the color produced by mixing the gases in atube and by introducing mercury or other elements. The stencil openingsin my device are uncovered or clear openings and a peculiar effect ofthe apparatus is an apparent creeping or rocking of the tubes which isan optical illusi on due to the inability of the eye to follow rapidmotion. This apparent rocking of the several tubes causes the lines oflight issuing from the tubes to cross each other,

as indicated at 16 in Fig. 5, the result being that the letters or othercharacters are apparently covered with a net of coarse mesh andconsisting ofinterse'cting lines of light.

It is to be particularly noted that the pres-.

ent construction provides units which are standardized and may,therefore, be pro duced in' any quantity without waiting for a specialdemand and these standardized units may be employed in any sign. If atube should be broken, it is not necessary to take the sign out ofcommission, as a reserve supply of the standardized units may be kept onhand and in order to replace a broken unit it is necessary merely toremove the screws 15 retaining the panel'carrying that unit in place sothat the panel and the'unit may lFWithdrawn' from the supporting head, anew unit quickly placed in position on the panel and the panel thenreinserted and se- It is also to be noted that the sign mission for anyprotracted period of time and also without requiring a completedismantling and rebuilding of the sign. To'

change the sign, all that is necessary is to remove the stencil or capplate 9 and sub- 'stitute therefor another cap plate having differentcharacters formed therethrough.

B using a stencilin connection with the luminescent tubesfnot only maythe wording on the display sign be changed at will but the width of theletters or characters maybe varied at will so as to permit the displayof characters much wider than the diameter of the luminescent tubes.Moreover, when the letters of the Word being displayed are maderelatively wide, it will be impossible to distinguish the luminescenttubes through the openings in the stencil as all the observer will seeis the delineation of the letters or characters in a brilliantlight'efi'ect.

. Having thus described the invention, 1 claim:

1. A changeable display device comprising a head rotatable about its owncenter as an axle, a luminescent tube secured upon said head, and a capplaterotatable with the head fitted over the tube and havingcharacterforming openings cut therethrough.

2. A changeable display device comprising a rotatable head, aluminescent tube removably mounted upon the head and consisting of aplurality of closely arranged substantially parallel sections connectedat their opposite ends alternately, the electrode terminals of the tubebeing disposed entirely within the plane of said parallel sections ofthe tube, and a stencil plate secured upon the head over the tube.

a head rotatable about its own center as an' axis, a panel removablysecured upon the head, a luminescent tube carried by said panel, and astencil plate secured upon the head over thepanel.

4. A changeable display device comprising a head rotatable about its owncenter as an axis and having a marginal rim, and a plurality ofpartitions whereb the partitions and the rim will define a p urality ofcompartments, a luminescent tube mounted in each of said compartments,and'a'stencil plate secured upon the rim and extending over thepartitions and having character-forming openings cut therethroughcoordinated with the respective compartments. 7

5. A changeable display device comprising a rotatable head havingail-outstanding marginal flange, a plurality of panels detachablysecured to the display face of the, head, a luminescent tube secured toeach panel and disposed entirely within the lines of the flange, and astencil plate detachably secured to the flange and covering the tubes.

6. A changeable display device comprising a head rotatable about its owncenter as an axis, panels detachably secured to the display luminoustube mounted on the head between face of the head, a luminescent tubesecured said head and stencil plate and rotatable to each panel andbodily removable with the therewith.

panel from the head, and an opaque cap plate removably secured to thehead over the tubes and having character-forming openings cuttherethrough.

7. A changeable display device comprising a head rotatable about its owncenter as an axis, a plurality of banks of luminescent tubes detachablysecuredto the head, and an opaque cap plate detachably secured to thehead and having character-forming openings cut therethrough to permitthe unob structed light rays from each bank of tubes to be directlyvisible through the openings.

8. A changeable display device comprising ahead rotatable about its owncenter as an axis, a plurality of panels'detachably secured to thedisplay face of the head, supports carried by the panels, luminescenttubes seated in said supports and bodily removable from the head withthe panels, and an opaque stencil plate detachably secured to the headand covering the tubes.

9. A changeable display device comprising a rotatable head having anoutstanding marginal flange, partitions extending across the displayface of the head and connected with and of substantially the same Widthas the flange, removable panels detachably secured to the head betweenthe partitions, a plurality of banks of luminescent tubes, one bankbeing permanently secured to each panel, and a cap plate detachablysecured to the marginal flange of the head and covering the severalbanks of tubes, said capplate having clear character-forming openingsout therethrough.

' 10. A changeable display device comprising a rotatable head, panelsdetachably se-' cured to the display face of the head, a coiledluminescent tube secured to and carried by each panel with the terminalsof each coil disposed parallel with the adjacent surface of the panel,and a cap plate detachably secured to the head and extending over theseveral tubes, said cap plate having character-forming openings cuttherethrough opposite each coil.

11. A changeable sign comprising a head rotatable about its own centeras an axis, a panel detachably secured to the front face of the head, astencil plate disposed in front of and spaced from the panel, and adisplay unit comprising a luminescent tube bent into a coil parallelwith the adjacent surface of the panel and permanently secured theretoat predetermined points to equalize the strain of centrifugal force whenthe head is rotated.

12. A changeable sign comprising a head and a stencil plate rotatabletogether about a common center in parallel planes, and a

